The average 13-year-old boy is 61.5 inches tall, while the average 13-year-old girl is 61.7 inches tall. It is important to note that individual height can vary drastically from these averages depending on genetics and family background.
In general, a baseline for average teenage height is hard to determine. During the adolescent years, a child's body experiences growth spurts that lead to major changes in both height and weight. Thus, there are flaws in most statistics on average teenage height, as the height of a 13-year-old changes quickly. Girls in particular experience dramatic changes in height, weight and body-fat distribution during the early teen years.